Dmytryshyn, M.I., and O.V. Lopushansky. “Lorentz Type Spaces of Ultrasmooth Vectors of Closed Operators”. Carpathian Mathematical Publications 1, no. 1 (June 30, 2009): 8–14. Accessed May 20, 2024. https://journals.pnu.edu.ua/index.php/cmp/article/view/4000.